Nickelocene-Filled Purely Metallic Single-Walled Carbon Nanotubes: Sorting and Tuning the Electronic Properties.

Marianna V Kharlamova

doi:10.3390/nano11102500

Abstract

We conducted the filling of single-walled carbon nanotubes (SWCNTs) with nickelocene molecules and separation of the filled SWCNTs by conductivity type by density-gradient ultracentrifugation. We tailored the electronic properties of nickelocene-filled purely metallic SWCNTs by thermal treatment in high vacuum. Our results demonstrated that annealing at low temperatures (360–600 °C) leads to n-doping of SWCNTs, whereas annealing at high temperatures (680–1200 °C) results in p-doping of SWCNTs. We found a correlation between the chemical state of the incorporated substances at different annealing temperatures and its influence on the electronic properties of SWCNTs.

Highlights

Carbon nanotubes, one-dimensional allotropic modifications of carbon with sp2 hybridization of atoms, can be envisaged as graphene sheets rolled into cylinders
The spectra of all samples include a single peak, which is positioned at a binding energy of 284.73 eV for nickelocenefilled SWCNTs
The annealing of the filled SWCNTs leads to the shift of the peak

Summary

Introduction

One-dimensional allotropic modifications of carbon with sp hybridization of atoms, can be envisaged as graphene sheets rolled into cylinders. Depending on the number of graphene layers, the nanotubes are classified as single- (SWCNT), double- (DWCNT) and multi-walled. SWCNTs are attracting the attention of researchers thanks to their unique physical and chemical properties, which can be applied in different fields. SWCNTs are promising materials for the generation of nanoelectronic devices [1]. The properties of SWCNTs are defined by their atomic structure. Contemporary synthesis methods allow preparing the mixture of nanotubes with different structures and properties, limiting their application [2]

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Results

Conclusion